1. Field of the Invention
The invention relates generally to spacers within microelectronic structures. More particularly, the invention relates to methods for controlling spacer linewidth within microelectronic structures.
2. Description of the Related Art
Semiconductor structures typically include semiconductor substrates within and upon which are located and formed semiconductor devices, such as but not limited to resistors, transistors, diodes and capacitors. The semiconductor devices are connected and interconnected using patterned conductor layers that are separated by dielectric layers.
A particular sub-structure that may be used within a semiconductor structure as an adjunct to any or all of the foregoing semiconductor devices is a spacer. A spacer typically comprises three sides in cross-section, where two of the three sides are perpendicular and the remaining side of the three sides outwardly curves and connects the other two sides that are perpendicular. Spacers are often located and formed adjoining nominally perpendicular sidewalls of semiconductor device features. Such a spacer may often be used, for example, for purposes of separating and isolating a contact region portion of a semiconductor device from other portions of the semiconductor device. Spacers are generally formed using blanket spacer material layer deposition and anisotropic etchback method that provides the spacer of the foregoing three-sided shape. Although not specifically so limited, spacers also generally comprise dielectric materials.
Spacers are a desirable feature within semiconductor structures, due to their ability to effectively horizontally isolate components within semiconductor structures. However, in order to effectively serve such a function, spacers are often desirably or necessarily fabricated with a uniform linewidth.
To that end, desirable are linewidth controlled spacers and methods for fabricating linewidth controlled spacers.